REVIEW Recent advances in electroless-plated Ni-P and its composites for erosion and corrosion applications: a review Eman M. Fayyad 1 & Aboubakr M. Abdullah 1 & Mohammad K. Hassan 1 & Adel M. Mohamed 2 & George Jarjoura 3 & Zoheir Farhat 3 Received: 10 April 2018 /Accepted: 30 July 2018 /Published online: 15 August 2018 # Springer Nature Switzerland AG 2018 Abstract The metallic coating of surfaces plays a vital role in the protection of most industrial applications. Coatings can be carried through various routes (e.g., mechanical and electrochemical plating techniques). Electroless nickel coatings present unparalleled prop- erties and a unique combination of corrosion and wear resistance features. Recently, the use and development of electroless nickel-phosphorus (ENP) coatings has attracted broad attention from many industries (e.g., oil and gas) due to their superior corrosion and wear resistance properties. In the present review article, mechanisms of ENP and preparation methods are briefly outlined. The review sheds light on properties of electroless Ni-P coatings and of their nanocomposites with an emphasis on new products and on their future development. Keywords Electroless Ni-P . Mechanism . Corrosion . Wear . Composite coatings 1 Introduction Corrosion is one of the major problems especially in the oil and gas industry. Therefore, pipelines, tanks, and similar equipment require regular maintenance because of corrosion and its associated problems. Consequently, the need for im- proving the corrosion protection of the metals has motivated the researchers to find superb new coatings or modify the existing ones. Electro, electroless, and mechanical plating in addition to hot dipping are the most frequently used tech- niques for metallic coatings. However, the unique properties of the electroless-plated coatings and the easiness of the handling process make this type of plating the most market- able method. Electroless Ni-P (ENP) coatings represent over 95% of industrial electroless coatings. Generally, depending on phosphorus content levels, electroless Ni-P coatings are divided into three categories: low, medium, and high P at 1–7 wt%, 7–10 wt%, and 10–12 wt%, respectively. High phosphorus content Ni-P coating is known for its excellent wear and corrosion resistance. The metallurgical properties of alloys are also dependent on percentages of phosphorus. More studies have been conducted on electroless Ni-P nanocomposites in recent decades. Ni-P-SiC, Ni-P-TiO 2 , Ni-P-Al 2 O 3 , and Ni-P-CNT are successful examples that have attracted attention owing to the improved properties relative to the original Ni-P coatings. This critical review article will not only help researchers to recognize the recent developments in ENP and metallic com- posite coating development, but it also recommends the con- ditions to be considered to enhance the applications of this type of coating in the erosion and corrosion fields. The article includes a comparison between the recent work that took place in the last 5 years, including the used nanoparticles and metals in the ENP composites, the bath conditions, and the used techniques in addition to highlighting the new technologies that are being used. * Eman M. Fayyad emfayad@qu.edu.qa * Aboubakr M. Abdullah abubakr2@yahoo.com 1 Center for Advanced Materials, Qatar University, P.O. Box 2713, Doha, Qatar 2 Department of Metallurgical and Materials Engineering, Faculty of Petroleum and Mining Engineering, Suez University, Box 43721, Suez, Egypt 3 Department of Process Engineering and Applied Science, Materials Engineering Program, Dalhousie University, Halifax, Nova Scotia B3J 2X4, Canada Emergent Materials (2018) 1:3–24 https://doi.org/10.1007/s42247-018-0010-4